Split stream fracturing methods are disclosed in U.S. Pat. No. 3,842,910 (Zingg), U.S. Pat. No. 2,876,839 (Fast), U.S. Pat. No. 7,845,413 (Shampine), U.S. Pat. No. 7,341,103 (Taylor), and U.S. Pat. No. 5,899,272 (Loree) and US publication no. 20090301719 (Bull). Such methods combine a proppant stream and a fracturing fluid stream after pumping both streams with frac pressure pumps but before the streams enter the wellhead, including at or near the wellhead, and it is known from these and other references to use liquefied petroleum gas (LPG) as a fracturing fluid.